Stabilizer thiirane derivatives containing hindered phenol groups

ABSTRACT

Compounds of the formula I    &lt;IMAGE&gt;  (I)  in which R1 and R2, independently, denote alkyl with 1 to 6 carbon atoms, cycloalkyl with 5 to 8 carbon atoms, allyl, methallyl, aralkyl with 5 to 9 carbon atoms, phenyl, 1- or 2-naphthyl, or alkaryl with 7 to 9 carbon atoms, R2 moreover also denotes hydrogen, R3 denotes hydrogen, alkyl with 1 to 6 carbon atoms, unsubstituted phenyl or phenyl substituted by one or two chlorine atoms and/or one or two methyl groups, B denotes a hetero atom, the group -OC(O)-, -OC(O)-CH2CH2- or a direct bond, m is an integer from 0 to 6, and n is an integer from 1 to 6, are prepared by reaction of a thioglycerol derivative with a carboxylic acid containing the hindered phenol moiety in the presence of an acid and are used as antioxidants and thermal stabilizers for lubricating oils, plastics, resins and other organic substrates.

This application is a continuation of application Ser. No. 836,361,filed Mar.5, 1986, now abandoned, which is a divisional of applicationSer. No. 773,723 filed on Sept. 9, 1985, now U.S. Pat. No. 4,617,404.

The present invention relates to a process for preparing thiiranecompounds, to the use of such compounds as stabilizers for organicpolymers and lubricants, as well as to new thiiranes.

Sterically hindered phenols containing a thiirane moiety are knowncompounds and are described, for example, in U.S. Pat. No. 3,992,420.These compounds are manufactured by reaction of the correspondingoxirane derivatives with thiourea or an alkali metal thiocyanate in asolvent, the oxirane being prepared from the corresponding olefins byreaction with percarboxylic acids or from alkali phenoxides andepichlorohydrins. These methods involve a two-step process and the useof several intermediates and reagents. Furthermore, the overall yieldobtained according to these processes and the purity of the resultingend products are, in many instances, unsatisfactory.

Other thiirane compounds absent the hindered phenol group and processesfor the preparation thereof are disclosed in U.S. Pat. Nos. 3,359,298,3,404,158, Lautenschlaeger et al., J. Org. Chem. 34(12), 3991-8 (1969)and Zh. Org. Khim. 12(3), 562-565 (1976).

The present invention provides a process for the production of thiiranecompounds having the formula I ##STR2## in which R₁ and R₂,independently, denote alkyl with 1 to 6 carbon atoms, cycloalkyl with 5to 8 carbon atoms, allyl, methallyl, aralkyl with 5 to 9 carbon atoms,phenyl, 1- or 2-naphthyl or alkaryl with 7 to 9 carbon atoms, R₂moreover also denotes hydrogen, R₃ denotes hydrogen, alkyl with 1 to 6carbon atoms, unsubstituted phenyl or phenyl substituted by one or twochlorine atoms and/or one or two methyl groups, B is a hetero atom, thegroup --OC(O)--, --OC(O)--CH₂ CH₂ -- or a direct bond, m is an integerfrom 0 to 6, and n is an integer from 1 to 6, which comprises reacting acompound of the formula II ##STR3## with a thioglycerol of the formulaIII ##STR4## werein R₁, R₂, R₃, B, m and n are defined as above, in thepresence of a catalytic amount of an acid, with or without an inertorganic solvent.

In the definition of the compounds of formula I, R₁, R₂ and R₃ can bealkyl with 1 to 6 carbon atoms such as, for example, methyl, ethyl,propyl, isopropyl, n-butyl, sec.-butyl, tert.-butyl, amyl, sec.-amyl,tert.-amyl, hexyl or 1,1-dimethylbutyl. Preferably alkyl for R₁ isiso-propyl, sec.-butyl, tert.-butyl, iso-amyl and 1,1-dimethylbutyl, andmost preferably tert.-butyl. Preferred alkyl for R₂ is methyl andtert.-butyl.

R₁ and R₂ can also be a cycloalkyl group with 5 to 8 carbon atoms suchas, for example, cyclopentyl, cyclohexyl, α-methylcyclohexyl orcyclohexyl, or an aralkyl group with 5 to 9 carbon atoms, such as, forexample, benzyl α-phenylethyl or α,α-dimethylbenzyl. Preferred arecyclohexyl and benzyl.

R₁ and R₂ can also be alkaryl with 7 to 9 carbon atoms such as, forexample, o-, m- or p-tolyl, 2,3-, 2,4-, 2,5-, 2,6-, 3,4- or3,5-dimethylphenyl, 2,3,4-, 2,3,5-, 2,3,6-, 2,4,5-, 2,4,6-, 2,5,6- or3,4,5-trimethylphenyl. Preferred alkaryl for R₁ and R₂ are o-, m- andp-tolyl.

B can be a hetero atom such as, for example --O--, --S-- and --NH--.

Preferably m is 2 and n is 1.

If R₃ denotes phenyl substituted by one or two chlorine atoms and/ormethyl groups, it can be, for example, p-chloro- or p-methyl-phenyl and2-methyl-5-chlorophenyl.

Preferred compounds of formula I are those in which R₁ and R₂,independently of one another, denote alkyl with 1 to 4 carbon atoms,cycloalkyl or α-methylbenzyl, R₂ moreover also denotes hydrogen, R₃ ishydrogen or methyl, B is a direct bond, m is the number 2 and n denotes1.

Particularly preferred compounds of the formula I are those in which R₁is tert.-butyl, R₂ is in the ortho position to the hydroxy group anddenotes hydrogen, methyl or tert.-butyl, R₃ is hydrogen, B is a directbond, m is 2 and n is 1.

For illustration purposes some specific examples of compounds offormulae II and III are listed. These compounds are generally availableas items of commerce or can be manufactured according to known methodsof preparation.

Compounds of formula II:

3,5-dimethyl-4-hydroxybenzene-propionic acid

3-methyl-5-tert.-butyl-4-hydroxybenzene-propionic acid

3,5-di-isopropyl-4-hydroxybenzene-propionic acid

3,5-di-tert.-butyl-4-hydroxybenzene-propionic acid

3,5-di-tert.-pentyl-4-hydroxybenzene-propionic acid

3,5-di-tert.-butylbenzylic acid

3,5-di-tert.-butylbenzoic acid

3,5-di-tert.-butylbenzylthioacetic acid

β-(3,5-di-tert-butylbenzylthio)-propionic acid

3,5-di-tert.-butylbenzyloxyacetic acid

Compounds of formula III:

1-thioglycerol

3-mercapto-3-methyl-1,2-propan-diol

The instant process is carried out by mixing a compound of the formulaII and a compound of the formula III in the presence of an acid, withoutor with an inert organic solvent.

The reaction can be carried out at various temperatures, preferably at atemperature range from 20° C. to 200° C., more preferably from 50° to150° C. and most preferably from 80° to 110° C. It can be conducted atatmospheric pressure or under pressure.

Inert organic solvents can be, for example, aliphatic or aromatichydrocarbons such as hexane, heptane, cyclohexane, benzene or benzenesubstituted by alkyl, alkoxy or halogen, e.g. toluene, xylenes,anisoles, chlorobenzene or dichlorobenzenes, and nitrobenzene; ketonessuch as cyclohexanone; ethers such a tetrahydrofuran or dioxane; glycolethers such as ethylene glycol dimethyl or diethyl ether; amides such asdimethylformamide, dimethylacetamide or N-methylpyrrolidone; nitrilessuch as acetonitrile; and also dimethylsulfoxide or sulfolane. Mixturesof the above-mentioned solvents can also be used. Preferred solvents aretoluene, xylene or halogen-substituted benzene.

The process of the present invention is conducted in the presence of anacid. Examples of suitable acids are aliphatic or aromatic carboxylic orsulfonic acids, e.g. formic acid, acetic acid, propionic acid, oxalicacid, benzoic acid, methane sulfonic acid, benzene sulfonic acid orp-toluene sulfonic acid. Further suitable acids include mineral acidssuch as hydrochloric acid, sulfuric acid or phosphoric acid.

In the process of this invention, the strong acid may be employed in acatalytic amount, preferably 0.001 to 0.20 moles, more preferably 0.02to 0.10 moles, based on one mole of the compound of the formula II.Compounds of formula II and III are employed in a stoichiometric amount,an excess of the compound of formula III often having an advantageousinfluence on the yield.

The water formed during the course of the reaction can be removedcontinuously by azeotropic distillation. The products of the formula Iobtained by the process of the invention can be isolated by usualmethods such as decantation, extraction, or distillation preferablyunder diminished pressure. Depending on the envisaged end-use, it may beadvantageous to use the crude resulting product or to purify it bydistillation or crystallization from an organic solvent.

For the reaction of a compound of formula II with a compound of formulaIII, one may charge the reaction vessel, at low temperatures, with allthe components and then heat the mixture to the desired reactiontemperature, or add the individual components to each other within theindicated range of reaction temperatures. A preferred embodiment of thereaction consists in charging the reaction vessel with the compound ofthe formula II and the acidic catalyst and then adding the compound ofthe formula III at the desired reaction temperature. A furtherpossibility consists in adding compounds of formulae II and IIIsimultaneously to the acid. It is also possible to carry out the processof the invention batchwise or continuously.

The present invention also relates to new compounds of the formula IV##STR5## wherein R₄ and R₅, independently, denote alkyl with 1 to 6carbon atoms, cycloalkyl with 5 to 8 carbon atoms, allyl, methallyl,aralkyl with 5 to 9 carbon atoms, R₅ moreover also denotes hydrogen, mis an integer from 0 to 6, n is an integer from 1 to 6, B₁ denotes ahetero atom, the group --OC(O)--, --OC(O)--CH₂ --CH₂ -- or a directbond, and R₆, when B₁ is a direct bond, denotes unsubstituted phenyl orphenyl substituted by one or two chlorine atoms and/or one or two methylgroups, or R₆, when B₁ is a hetero atom, the group --OC(O)-- or thegroup --OC(O)--CH₂ --CH₂ --, denotes hydrogen, alkyl with 1 to 6 carbonatoms, unsubstituted phenyl or phenyl substituted by one or two chlorineatoms and/or one or two methyl groups.

The compounds of the formulae I and IV according to this invention areparticularly effective in stabilizing organic materials such asplastics, polymers and resins, mineral and synthetic fluids such aslubricating oils, circulating oils, etc. against oxidative, thermal oractinic degradation.

Substrates in which the compounds of the formulae I and IV according tothis invention are particularly useful are polyolefins such aspolyethylene and polypropylene; polystyrene, including impactpolystyrene, ABS resin, SBR, isoprene, as well as natural rubber,polyesters including polyethylene terephthalate and polybutyleneterephthalate, including copolymers, and lubricating oils such as thosederived from mineral oil.

In general polymers which can be stabilized include:

1. Polymers of monoolefins and diolefins, for example polyethylene(which optionally can be crosslinked), polypropylene, polyisobutylene,polybutene-1, polymethylpentene-1, polyisoprene or polybutadiene, aswell as polymers of cycloolefins, for instance of cyclopentene ornorbornene.

2. Mixtures of the polymers mentioned under (1), for example mixtures ofpolypropylene with polyisobutylene.

3. Copolymers of monoolefins and diolefins with each other or with othervinyl monomers, such as, for example, ethylene/propylene,propylene/butene-1, propylene/isobutylene, ethylene/butene-1,propylene/butadiene, isobutylene/isoprene, ethylene/alkyl acrylates,ethylene/alkyl methacrylates, ethylene/vinyl acetate or ethylene/acrylicacid copolymers and their salts (ionomers) and terpolymers of ethylenewith propylene and a diene, such as hexadiene, dicyclopentadiene orethylidene-norbornene.

4. Polystyrene, poly-(p-methylstyrene).

5. Copolymers of styrene or α-methylstyrene with dienes or acrylicderivatives, such as, for example, styrene/butadiene,styrene/acrylonitrile, styrene/ethyl methacrylate,styrene/butadiene/ethyl acrylate, styrene/acrylonitrile/methyl acrylate;mixtures of high impact strength from styrene copolymers and anotherpolymer, such as, for example, from a polyacrylate, a diene polymer oran ethylene/propylene/diene terpolymer; and block polymers of styrene,such as, for example, styrene/butadiene/styrene,styrene/isoprene/styrene, styrene/ethylene/butylene/styrene orstyrene/ethylene/propylene/styrene.

6. Graft copolymers of styrene, such as, for example, styrene onpolybutadiene, styrene and acrylonitrile on polybutadiene, styrene andalkyl acrylates or methacrylates on polybutadiene, styrene andacrylonitrile on ethylene/propylene/diene terpolymers, styrene andacrylonitrile on polyacrylates or polymethacrylates, styrene andacrylonitrile on acrylate/butadiene copolymers, as well as mixturesthereof with the copolymers listed under (5), for instance the copolymermixtures known as ABS-, MBS-, ASA- or AES-polymers.

7. Halogen-containing polymers, such as polychloroprene, chlorinatedrubbers, chlorinated or sulfochlorinated polyethylene, epichlorohydrinehomo- and copolymers, polymers from halogen-containing vinyl compounds,as for example, polyvinylchloride, polyvinylidene chloride, polyvinylfluoride, polyvinylidene fluoride, as well as copolymers thereof, as forexample, vinyl chloride/vinylidene chloride, vinyl chloride/vinylacetate or vinylidene chloride/vinyl acetate copolymers.

8. Polymers which are derived from α,β-unsaturated acids and derivativesthereof, such as polyacrylates and polymethacrylates, polyacrylamide andpolyacrylonitrile.

9. Copolymers from the monomers mentioned under (8) with each other orwith other unsaturated monomers, such as, for instance,acrylonitrile/butadien, acrylonitrile/alkyl acrylate,acrylonitrile/alkoxyalkyl acrylate or acrylonitrile/vinyl halogenidecopolymers or acrylonitrile/alkyl methacrylate/butadiene terpolymers.

10. Polymers which are derived from unsaturated alcohols and amines, oracyl derivatives thereof or acetals thereof, such as polyvinyl alcohol,polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinylmaleate, polyvinylbutyral, polyallyl phthalate or polyallyl-melamine.

11. Homopolymers and copolymers of cyclic ethers, such as polyalkyleneglycols, polyethylene oxide, polypropylene oxide or copolymers thereofwith bis-glycidyl ethers.

12. Polyacetals, such as polyoxymethylene and those polyoxymethyleneswhich contain ethylene oxide as comonomer.

13. Polyphenylene oxides and sulfides, and mixtures of polyphenyleneoxides with polystyrene.

14. Polyurethanes which are derived from polyethers, polyesters orpolybutadiens with terminal hydroxyl groups on the one side andaliphatic or aromatic polyisocyanates on the other side, as well asprecursors thereof (polyisocyanates, polyols or prepolymers).

15. Polyamides and copolyamides which are derived from diamines anddicarboxylic acids and/or from aminocarboxylic acids or thecorresponding lactams, such as polyamide 4, polyamide 6, polyamide 6/6,polyamide 6/10, polyamide 11, polyamide 12,poly-2,4,4-trimethylhexamethylene terephthalamid or poly-m-phenyleneisophthalamide, as well as copolymers thereof with polyethers, such asfor instance with polyethylene glycol, polypropylene glycol orpolytetramethylene glycols.

16. Polyureas, polyimides and polyamide-imides.

17. Polyesters which are derived from dicarboxylic acids and diolsand/or from hydroxycarboxylic acids or the corresponding lactones, suchas polyethylene terephthalate, polybutylene terephthalate,poly-1,4-dimethylol-cyclohexane terephthalate,poly-[2,2-(4-hydroxyphenyl)-propane] terephthalate andpolyhydroxybenzoates as well as block-copolyether-esters derived frompolyethers having hydroxyl end groups.

18. Polycarbonates.

19. Polysulfones, polyethersulfones and polyetherketones.

20. Crosslinked polymers which are derived from aldehydes on the onehand and phenols, ureas and melamines on the other hand, such asphenol/formaldehyde resins, urea/formaldehyde resins andmelamine/formaldehyde resins.

21. Drying and non-drying alkyd resins.

22. Unsaturated polyester resins which are derived from copolyesters ofsaturated and unsaturated dicarboxylic acids with polyhydric alcoholsand vinyl compounds as crosslinking agents, and also halogen-containingmodifications thereof of low inflammability.

23. Thermosetting acrylic resins, derived from substituted acrylicesters, such as epoxy-acrylates, urethane-acrylates or polyesteracrylates.

24. Alkyd resins, polyester resins or acrylate resins in admixture withmelamine resins, urea resins, polyisocyanates or epoxide resins ascrosslinking agents.

25. Crosslinked epoxide resins which are derived from polyepoxides, forexample from bis-glycidyl ethers or from cycloaliphatic diepoxides.

26. Natural polymers, such as cellulose, rubber, gelatine andderivatives thereof which are chemically modified in a polymerhomologousmanner, such as cellulose acetates, cellulose propionates and cellulosebutyrates, or the cellulose ethers, such as methylcellulose.

27. Mixtures of polymers as mentioned above, for example PP/EPDM,Polyamide 6/EPDM or ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS, PBTP/ABS.

28. Naturally occuring and synthetic organic materials which are puremonomeric compounds or mixtures of such compounds, for example mineraloils, animal and vegetable fats, oil and waxes, or oils, fats and waxesbased on synthetic esters (e.g. phthalates, adipates, phosphates ortrimellithates) and also mixtures of synthetic esters with mineral oilsin any weight ratios, which materials may be used as plasticizer forpolymers or as textile spinning oils, as well as aqueous emulsions ofsuch materials.

29. Aqueous emulsions of natural or synthetic rubber, e.g. natural latexor latices of carboxylated styrene/butadiene copolymers.

In general, the compounds of the formulae I and IV according to thisinvention are employed in from about 0.01 to about 5% by weight of thestabilized composition, although this will vary with the particularsubstrate and application. An advantageous range is from about 0.5 toabout 2%, and especially 0.1 to about 1%.

The stabilizers of the instant invention may readily be incorporatedinto the organic polymers by conventional techniques, at any convenientstage prior to the manufacture of shaped articles therefrom. Forexample, the stabilizer may be mixed with the polymer in dry powderform, or a suspension or emulsion of the stabilizer may be mixed with asolution, suspension, or emulsion of the polymer. The resultingstabilized polymer compositions of the invention may optionally alsocontain various conventional additives, such as the following.

1. Antioxidants

1.1. Alkylated monophenols, for example,

2,6-di-tert.butyl-4-methylphenol

2-tert.butyl-4,6-dimethylphenol

2,6-di-tert.butyl-4-ethylphenol

2,6-di-tert.butyl-4-n-butylphenol

2,6-di-tert.butyl-4-i-butylphenol

2,6-di-cyclopentyl-4-methylphenol

2-(α-methylcyclohexyl)-4,6-dimethylphenol

2,6-di-octadecyl-4-methylphenol

2,4,6-tri-cyclohexylphenol

2,6-di-tert.butyl-4-methoxymethylphenol

1.2. Alkylated hydroquinones, for example,

2,6-di-tert.butyl-4-methoxyphenol

2,5-di-tert.butyl-hydroquinone

2,5-di-tert.amyl-hydroquinone

2,6-diphenyl-4-octadecyloxyphenol

1.3. Hydroxylated thiodiphenyl ethers, for example

2,2'-thio-bis-(6-tert.butyl-4-methylphenol)

2,2'-thio-bis-(4-octylphenol)

4,4'-thio-bis-(6-tert.butyl-3-methylphenol)

4,4'-thio-bis-(6-tert.butyl-2-methylphenol)

1.4. Alkyliden-bisphenols, for example,

2,2'-methylene-bis-(6-tert.butyl-4-methylphenol)

2,2'-methylene-bis-(6-tert.butyl-4-ethylphenol)

2,2'-methylene-bis-[4-methyl-6-(α-methylcyclohexyl)-phenol]

2,2'-methylene-bis-(4-methyl-6-cyclohexylphenol)

2,2'-methylene-bis-(6-nonyl-4-methylphenol)

2,2'-methylene-bis-[6-α-methylbenzyl)-4-nonylphenol]

2,2'-methylene-bis-[6-α,α-dimethylbenzyl)-4-nonylphenol]

2,2'-methylene-bis-(4,6-di-tert.butylphenol)

2,2'-ethylidene-bis-(4,6-di-tert.butylphenol)

2,2'-ethylidene-bis-(6-tert.butyl-4-isobutylphenol)

4,4'-methylene-bis-(2,6-di-tert.butylphenol)

4,4'-methylene-bis-(6-tert.butyl-2-methylphenol)

1,1-bis-(5-tert.butyl-4-hydroxy-2-methylphenyl)-butane

2,6-di-(3-tert.butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol

1,1,3-tris-(5-tert.butyl-4-hydroxy-2-methylphenyl)-butane

1,1-bis-(5-tert.butyl-4-hydroxy-2-methylphenyl)3-n-dodecylmercaptobutane

ethyleneglycol-bis-[3,3-bis-(3'-tert.butyl-4'-hydroxyphenyl)-butyrate]

di-(3-tert.butyl-4-hydroxy-5-methylphenyl)-dicyclopentadiene

di-[2-(3'-tert.butyl-2'-hydroxy-5'-methyl-benzyl)-6-tert.butyl-4-methylphenyl]-terephthalate.

1.5. Benzyl compounds, for example,

1,3,5-tri-(3,5-di-tert.butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene-di-(3,5-di-tert.butyl-4-hydroxybenzyl)sulfide

3,5-di-tert.butyl-4-hydroxybenzyl-mercapto-acetic acid isooctyl ester

bis-(4-tert.butyl-3-hydroxy-2,6-dimethylbenzyl)dithiolterephthalate

1,3,5-tris-(3,5-di-tert.butyl-4-hydroxybenzyl)-isocyanurate

1,3,5-tris-(4-tert.butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate

3,5-di-tert.butyl-4-hydroxybenzyl-phosphoric acid dioctadecyl ester

3,5-di-tert.butyl-4-hydroxybenzyl-phosphoric acid monoethyl ester,calcium-salt

1.6. Acylaminophenols, for example,

4-hydroxy-lauric acid anilide

4-hydroxy-stearic acid anilide

2,4-bis-octylmercapto-6-(3,5-tert.butyl-4-hydroxyanilino)-s-triazine

octyl-N-(3,5-di-tert.butyl-4-hydroxyphenyl)-carbamate

1.7. Esters of β-(3,5-di-tert.butyl-4-hydroxyphenyl)-propionic acid withmonohydric or polyhydric alcohols, for example,

    ______________________________________                                        methanol       diethyleneglycol                                               octadecanol    triethyleneglycol                                              1,6-hexanediol pentaerythritol                                                neopentylglycol                                                                              tris-hydroxyethyl isocyanurate                                 thiodiethyleneglycol                                                                         di-hydroxyethyl oxalic acid diamide                            ______________________________________                                    

1.8. Ester of β-(5-tert.butyl-4-hydroxy-3-methylphenyl)-propionic acidwith monohydric or polyhydric alcohols, for example,

    ______________________________________                                        methanol       diethyleneglycol                                               octadecanol    triethyleneglycol                                              1,6-hexanediol pentaerythritol                                                neopentylglycol                                                                              tris-hydroxyethyl isocyanurate                                 thiodiethyleneglycol                                                                         di-hydroxyethyl oxalic acid diamide                            ______________________________________                                    

1.9. Amides of β-(3,5-di-tert.butyl-4-hydroxyphenyl)-propionic acid forexample,

N,N'-di-(3,5-di-tert.butyl-4-hydroxyphenylpropionyl)hexamethylendiamine

N,N'-di-(3,5-di-tert.butyl-4-hydroxyphenylpropionyl)trimethylendiamine

N,N'-di-(3,5-di-tert.butyl-4-hydroxyphenylpropionyl)hydrazine

2. UV Absorbers and Light Stabilisers

2.1. 2-(2'-Hydroxyphenyl)-benztriazoles, for example, the 5'-methyl-,3',5'-di-tert.butyl-, 5'-tert.butyl-, 5'-(1,1,3,3-tetramethylbutyl)-,5-chloro-3',5'-di-tert.butyl-, 5-chloro-3'-tert.butyl-5'-methyl-, 3'-sec.butyl-5'-tert.butyl-, 4'-octoxy, 3',5'-di-tert.amyl-, 3',5'-bis-(α,α-dimethylbenzyl)-derivative.

2.2. 2-Hydroxy-benzophenones, for example, the 4-hydroxy-, 4-methoxy-,4-octoxy, 4-decyloxy-, 4-dodecyloxy-, 4-benzyloxy, 4,2',4'-trihydroxy-and 2'-hydroxy-4,4'-dimethoxy derivative.

2.3. Ester of optionally substituted benzoic acids for example, phenylsalicylate, 4-tert.butyl-phenylsalicilate, octylphenyl salicylate,dibenzoylresorcinol, bis-(4-tert.butylbenzoyl)-resorcinol,benzoylresorcinol, 3,5-di-tert.butyl-4-hydroxybenzoic acid2,4-di-tert.butyl-phenyl ester and 3,5-di-tert.-butyl-4-hydroxybenzoicacid hexadecyl ester.

2.4. Acrylates, for example, α-cyano-β,β-diphenylacrylic acid ethylester or isooctyl ester, α-carbomethoxy-cinnamic acid methyl ester,α-cyano-β-methyl-p-methoxy-cinnamic acid methyl ester or butyl ester,α-carbomethoxy-p-methoxycinnamic acid methyl ester,N-(β-carbomethoxy-β-cyanovinyl)-2-methyl-indoline.

2.5 Nickel compounds, for example, nickel complexes of2,2'-thio-bis-[4-(1,1,3,3-tetramethylbutyl)-phenol], such as the 1:1 or1:2 complex, optionally with additional ligands such as n-butylamine,triethanolamine or N-cyclohexyl-di-ethanolamine, nickeldibutyldithiocarbamate, nickel salts of4-hydroxy-3,5-di-tert.butylbenzylphosphonic acid monoalkyl esters, suchas of the methyl, ethyl or butyl ester, nickel complexes of ketoximessuch as of 2-hydroxy-4-methyl-phenyl undecyl ketoxime, nickel complexesof 1-phenyl-4-lauroyl-5-hydroxy-pyrazol, optionally with additionalligands.

2.6. Sterically hindered amines, for examplebis-(2,2,6,6-tetramethylpiperidyl)-sebacatebis-(1,2,2,6,6-pentamethylpiperidyl)-sebacaten-butyl-3,5-di-tert.butyl-4-hydroxybenzyl malonic acidbis-(1,2,2,6,6-pentamethylpiperidyl)ester, condensation product of1-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinicacid, condensation product ofN,N'-(2,2,6,6-tetramethylpiperidyl)-hexamethylendiamine and4-tert.octylamino-2,6-dichloro-1,3,5-s-triazine,tris(2,2,6,6-tetramethylpiperidyl)-nitrilotriacetate,tetrakis-(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarbonicacid, 1,1'(1,2-ethanediyl)-bis-(3,3,5,5-tetramethylpiperazinone).

0 2.7. Oxalic acid diamides, for example, 4,4'-di-octyloxyoxanilide,2,2'-di-octyloxy-5,5'-di-tert.butyl-oxanilide,2,2'-di-dodecyloxy-5,5'-di-tert.butyl-oxanilide,2-ethoxy2'-ethyl-oxanilide, N,N'-bis (3-dimethylaminopropyl)oxalamide,2-ethoxy-5-tert.butyl-2'-ethyloxanilide and its mixture with2-ethoxy-2'-ethyl-5,4'-di-tert.butyloxanilide and mixtures of ortho- andpara-methoxy- as well as of o- and p-ethoxy-disubstituted oxanilides.

3. Metal deactivators, for example, N,N'-diphenyloxalic acid diamide,N-salicylal-N'-salicyloylhydrazine, N,N'-bis-salicyloylhydrazine,N,N'-bis-(3,5-di-tert.butyl4-hydroxyphenylpropionyl)-hydrazine,3-salicyloylamino1,2,4-triazole, bis-benzyliden-oxalic acid dihydrazide.

4. Phosphites and phosphonites, for example, triphenyl phosphite,diphenylalkyl phosphites, phenyldialkyl phosphites,tri-(nonylphenyl)phosphite, trilauryl phosphite, trioctadecyl phosphite,di-stearyl-pentaerythrit diphosphite, tris-(2,4-di-tert.butylphenyl)phosphite, di-isodecylpentaerythrityl diphosphite,di-(2,4-di-tert.butylphenyl)pentaerythrityl diphosphite,tristearyl-sorbite triphosphite,tetrakis-(2,4-di-tert.butylphenyl)-4,4'-diphenylylenediphosphonite.

5. Compounds which destroy peroxide, for example, esters ofβ-thiodipropionic acid, for example the lauryl, stearyl, myristyl ortridecyl esters, mercapto-benzimidazole or the zinc salt of2-mercaptobenzimidazole, zinc-dibutyl-dithiocarbamate,dioctadecyldisulfide,pentaerythrityl-tetrakis(β-dodecylmercapto)-propionate.

6. Polyamide stabilisers, for example copper salts in combination withiodides and/or phosphorus compounds and salts of divalent manganese.

7. Basic co-stabilisers, for example, melamine, polyvinylpyrrolidone,dicyandiamide, triallyl cyanurate, urea derivatives, hydrazinederivatives, amines, polyamides, polyurethanes, alkali metal salts andalkaline earth metal salts of higher fatty acids for example Castearate, Zn stearate, Mg stearate, Na ricinoleate and K palmitate,antimony pyrocatecholate or zinc pyrocatecholate.

8. Nucleating agents, for example, 4-tert.butyl-benzoic acid, adipicacid, diphenylacetic acid.

9. Fillers and reinforcing agents, for example, calcium carbonate,silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate,metal oxides and hydroxydes, carbon black, graphite.

10. Other additives, for example, plasticizers, lubricants, emulsifiers,pigments, optical brighteners, flameproofing agents, anti-static agents,blowing agents and thiosynergists such as dilaurylthiodipropionate ordistearylthiodipropionate.

The following examples illustrate the embodiments of this invention. Inthese examples, all parts given are by weight unless otherwisespecified.

EXAMPLE 1 Synthesis of thiaglycidyl3-(3',5'-di-tert.-butyl4'-hydroxyphenyl)propionate

(a) A 500 ml, three-necked reaction flask is charged with 41.76 g (0.15mole) of 3-(3',5'-di-tert.-butyl-4'-hydroxyphenyl)propionic acid, 1.43 g(0.0075 mole) of p-toluene sulfonic acid and 270 ml of dried toluene.The resulting reaction mixture is stirred and heated to reflux and 17.84g (0.165 mole) of thioglycerol are added dropwise over a one hourinterval while stirring continuously. The water which forms is removedcontinuously by azeotropic distillation and caught in a Dean-Stark trap.After about 3 1/2 hours reaction at reflux, the starting carboxylic acidis essentially all consumed (TLC evidence). The obtained reactionmixture is cooled to room temperature, transferred to a 1 L. separatoryfunnel and washed with 100 ml of water. This is repeated with 3×100 mlof water, the final pH being 7.0. The toluene solution of the product iswashed with 2×100 ml of saturated brine and dried over molecular sievesfor 18 hours. Removal of the sieves by filtration and stripping of thesolvent under diminished pressure affords 45.8 g of yellow syrup (87%crude yield).

(b) 45.8 g of the crude product is dissolved in 250 ml of hot hexane andthe resulting solution is filtered to remove approximately 0.5 g ofinsoluble product. This hot hexane filtrate is then treated with 5.0 gof Fulment® 237 Decolorizing Agent for ˜30 minutes. The solution is thenfiltered hot, allowed to cool to room temperature, and stripped undervacuum. The residue (42.25 g) is redissolved in 150 ml of heptane andretreated with 4.2 g of Fulment® 237 while stirring and heating for 30minutes.

The resulting mixture is filtered warm, allowed to cool to roomtemperature and seeded (with authentic seeds of A18-106). While stirringgently, the product slowly crystallizes without oiling out. Filtrationaffords 18.9 g of the product of formula ##STR6## with a melting pointof 74°-79° C. and the following microanalysis:

Calculated for C₂₀ H₃₀ O₃ S: Found: C%, 68.53; H%, 8.63; S%, 9.15. C%,68.3; H%, 8.8; S%, 8.9.

EXAMPLE 2

The compound obtained according to Example 1b is evaluated in alubricating oil as a stabilizer and antioxidant under the following oiloxidation test. This test (standard version according to ASTM 2272,Rotary Bomb Oxidation Test), is carried out in the following manner. Anoil sample of 50 g of a 150N Paraffinic mineral oil is oxidized in anoxygen atmosphere, in a glass vessel, together with 5 ml of distilledwater and a polished, catalytically active Cu spiral washed withpetroleum ether, 0.25% by weight of the stabilizer according to Example1b being added.

The glass vessel is in a stainless steel bomb with a manometer. The bombrotates axially at 100 rpm, at an angle of 30° to the horizontal, in anoil bath at 150° C. The oxygen pressure is initially about 6 bars,before heating, increases to exactly 14 bars at 150° C. and remainsconstant until oxidation has started. The test has ended when there hasbeen a pressure decrease of 1.7 bars. The time is recorded in minutes.

    ______________________________________                                        Result                                                                                         Minutes until pressure                                       Stabilizer       decrease of 1.7 bars                                         ______________________________________                                        --                25                                                          according to Example 1b                                                                        250                                                          ______________________________________                                    

The increase in time for evidence of the pressure drop is indicative ofa good stabilizing effect.

What is claimed is:
 1. A composition of matter comprising a lubricatingoil subject to oxidative, thermal and actinic degradation stabilizedwith an effective stabilizing amount of a compound of the formula##STR7## wherein R₄ and R₅, independently, denote alkyl with 1 to 6carbon atoms, cycloalkyl with 5 to 8 carbon atoms, allyl, methallyl,aralkyl with 5 to 9 carbon atoms, R₅ moreover also denotes hydrogen, mis an integer from 0 to 6, n is an integer from 1 to 6, B₁ denotes--O--, --S-- or --NH--, the group --OC(O)--, --OC(O)--CH₂ --CH₂ -- or adirect bond, and R₆, when B₁ is a direct bond, denotes hydrogen, alkylwith 1 to 6 carbon atoms, unsubstituted phenyl or phenyl substituted bychlorine, methyl or chlorine and methyl.
 2. A method for stabilizing alubricating oil against oxidative, thermal and actinic degradation whichcomprises incorporating into said lubricating oil an effectivestabilizing amount of a compound of the formula ##STR8## wherein R₄ andR₅, independently, denote alkyl with 1 to 6 carbon atoms, cycloalkylwith 5 to 8 carbon atoms, allyl, methallyl, aralkyl with 5 to 9 carbonatoms, R₅ moreover also denotes hydrogen, m is an integer from 0 to 6, nis an integer from 1 to 6, B₁ denote --O--, --S-- or --NH--, the group--OC(O)--, --OC(O)--CH₂ --CH₂ -- or a direct bond, and R₆, when B₁ is adirect bond, denotes hydrogen, alkyl with 1 to 6 carbon atoms,unsubstituted phenyl or phenyl substituted by chlorine, methyl orchlorine and methyl.